Process for sawing logs.



PROCESS FOR SAWING LOGS. APPLICATION man sen. 15. m5.

Patented Jan. 8,1918.

fruwrzi'0ns UNITED STATES PATENT OFFICE.

JOHN EDVABD JOHANSSON, OF HELSINGFORS, AND CARL GUSTAF TIGEBSTEDT, 0F ELIMK, FINLAND, RUSSIA.

PBOCESS FOR SA'WING LOGS.

Specification of Letters Patent.

Patented Jan. 8, 19.18.

Application filed September 15, 1915. Serial No. 50,773.

To all whom it may concern:

Be it known that we, JOHN EDvAao JonANssoN, residing at I-lclsingfors, Finland, and CARL G'os'rar T IGIIRSII'IDT, residing at- Elimii, Finland, Russia, both subjects of the Emperor of Russia, have jointly invented a certain new Process for Sawing Logs. of which the following is a specification.

The object of the present invention is to provide an im 'n-oved process for sawing lengths of wood such as logs so as to obtain with the usual macl'iines. present in every sawmill. a much greater amount of sawed wood and wood available for export than could be obtained with the processes used up to the present time.

The annexed drawing illustrat s the difference between the new and the 0 \proo esses. Figures 1 to 1 show the sawing according to the new process. and Figs. 5 to 8, the same. according to the old process. the cuts in both cases being shown by means of dotted lines. For the purpose of greater clearness the length of the log as related to its thickness, is considerably smaller than it is in reali! Fig. 1 shows the log seen from the side. and the cuts in the same.

Fig. 5-? shows the log seen from the top end.

Fig. 3 shows one of the middle boards seen perpendicular to the plane in Fig. 1, and as the sawing of this board takes place according to the new process.

Fig. 4 shows the same board seen from the top end.

Fig. 5 shows the same log as Fig. 1, but the dotted lines indicate. how. the sawing takes place acrding to the old process.

Fig. 6 shows the log .from the top end.

Fig. 7 shows one of the middle boards seen perpendicular to the plane of Fig. 5 and sawedaccording to the former proc ess. and

. Fig.8 shows the same board seen the top end.

As is seen from Fig. 1, the log. according to the new process. is so sawed in the saw gate that the saw blades follow a line sub stantially parallel to-the side of the log A, as for instance side a, not as heretofore, parallel to a line connecting the middle points I) of the top end B and c of the root from end 0. On adjusting the 109; A in the sa framerarc is tohe taken that thcbutsidp saw hiade on the side a producing out o 0f the adjustment shall touch only the outside Wood of tin: log throughout the entire length of the latter. This board taken on the surface of the. log will be a refuseboard of the full length of the log. The heartwood is then out to suitable or necessary thickness as desired, as for instance by cuts a to 11.. Upon the other side of the adjustment there is arranged a sutlicicnt numher of saw blades to simultaneously in the some working trip. saw the entire excess D o l' lll Ion muard the root, and in case it is not prcicrr d to saw up this excess separately for i)()XlJO\I(l. laths. etc.

For the purpose of better comparison be.- twcen the sawing operation in Fig. 1 and that. in Fig. 5, we have shown the section D on the other side of the adjustmif" in Fig. 1 uncut. and the board thus ob become. refuse only at the unperie'nd B;

agina'thc sawing has. in this casedhringz the work to so guide the log: that the surface of the log is followed as in sawing straight logs. Tn this case it is preferable to follow the concave side of the loo. More markedly bent. logs are cut. into suitable. lengths.

In the case of cutting a log with four corners it is on the other hand adiusted in the first frame with the bend downward as usual.

Tn trimming (Fig. 3) the same idea is carriod out as in sawing is the first frame. that is. the trin'nniua operation is substantially parallel to the side fot the untrimincd board or plank. and there is cut ofi' so much that the trim'n'icd part F is an acute angled piece the length of the board or plank from which it wascut. The board is adiustcd as usual according to the tip measurement. and the trimmingsaw then cuts the entire conical shape F of the board ofl from the board. Thereby there is obtained almost all the refuse in one piece F lying to the right inFig. 3, which evidently is much more advantageous than to obtain the refuse as previously in two pieces located on opposite sides of the board. Out of-these pieces there are out then slating battens, broomsticks, laths, and the like.

The output in this operation of sawing, as is easily understandable, becomes consider ably greater than previouslytrom the fact that the greater portion of the cone shape of the log is obtained in the form of lumber.

Cdmparative experiments made and lasting for several weeks have shown that to produce a standard amount of: lumber, on the average only about 200 cubic feet of round 10;? was necessary by our invention, while on the other hand the old sawing process re quired 260 to 270 cubic feet' In both cases the refuse arising was not calculatedf More over, with the new sawing process there is still obtained about ten per cent. slatingbattens, lnooinsticlts, and the like.

What we claim is:--

1. The process of sawing tapered logs into boards and the like by roducing a plurality of parallel cuts therein, all the said cuts being substantially parallel with one side of the log, the said cuts compri. 'ing the width of available wood in the log full length, whereby the remaining ava lable wood in the log of less than full length is obtained in one piece, which is adapted for cutting into smaller piecesby further cuts parallel with the earller cuts.

2. The process oftrimming boards in the direction of their length by sawing the same by parallel cuts, each of which is substantially parallel with one of the inclined limiting surfaces of the board, whereby the remaining available wood is produced in one trian liar-shaped piece which is adapted for cutting into smaller pieces by further cuts parallel with the earlier cuts.

3. The process of sawing tapered logs into boards and the like by producing a plurality of parallel cuts therein, all the said cuts being sul'istantially parallel with one side of the log, the said cuts comprising the width of available Wood in the log of full length, whereby the ren'iaining available wood in the log of less than full length is obtained in one piece which is adapted for cutting into smaller pieces by further cuts parallel with the earlier cuts, and in trimming the boards so produced by sawing the same by parallel cuts each of which is sul'istantiall parallel with one of the inclined limiting surfaces of the board, whereby the remaining available wood is produced in one tri angular-shaped piece which is adapted for cutting into smaller pieces by further cuts parallel with the earlier cuts.

In witness whereof, we. have hereunto signed our names in the presence of two subseribin" Witnesses.

JO EDVARD JOHANSSON. RL GUSTAF TIGERSTEDT.

Witnsses:

TORSTAW Dismisses, J. NORDQVIST. 

